TrueScaleAudio
Compare speakers at true scale
Pick two speakers and see them side by side at their real-world size.
Front view — overlaid at true scale
Click either cabinet to swap A ↔ B · Reference height: 324 mm (32.4 cm) · 1 mm = 1.73 px
Polk Reserve R100vsCastle Richmond IV
The Polk Reserve R100 stands 32.4 cm tall — about 1.9 cm more than the Castle Richmond IV at 30.5 cm. On footprint the Castle Richmond IV is the wider cabinet (19.0 cm versus 16.7 cm). At 87 dB against 86 dB, the Castle Richmond IV is the easier load to drive and plays louder from the same amplifier. Low frequencies come from a 133 mm cone on the Polk Reserve R100 and a 150 mm cone on the Castle Richmond IV. Both land in a similar price bracket, around $730 a pair.
| A | B | |
|---|---|---|
| Manufacturer | Polk | Castle |
| Model | Polk Reserve R100 | Castle Richmond IV |
| Height | 324 mm | 305 mm |
| Width | 167 mm | 190 mm |
| Depth | 260 mm | 262 mm |
| Weight | 5.5 kg | 6.3 kg |
| Enclosure | bass-reflex-rear | bass-reflex-rear |
| Drivers | 1× 25 mm tweeter (Pinnacle ring radiator), 1× 133 mm mid-bass (Turbine cone) | 1× 150 mm mid-bass, 1× 32 mm tweeter (soft dome) |
| Frequency — low | 58 Hz | 58 Hz |
| Frequency — high | 39000 Hz | 22000 Hz |
| Sensitivity | 86 dB | 87 dB |
| Impedance | 4 Ω | 8 Ω |
| Recommended amp | 30–150 W | 25–100 W |
| MAP (USD) | $699 / pair | $760 / pair |
| Where to buy | Check availability ↗ | Check availability ↗ |
| Brand website | polkaudio.com ↗ | castle.uk.com ↗ |
| Product page | Open product page ↗ | Open product page ↗ |
Larger value highlighted in green. For low-frequency extension, lower Hz = greater bass reach, so the deeper side is highlighted.